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Question 1. Which data structure in MongoDB is analogous to a row in a relational database? A) Collection B) Document C) Database D) Index Answer: B Explanation: In MongoDB, a document is a set of key-value pairs that represents a single record, similar to a row in a relational database. Question 2. What is one primary advantage of MongoDB's document model over traditional relational models? A) Fixed schema design B) Supports complex joins efficiently C) Flexibility to store different structures in the same collection D) Enforces strict data types across all documents Answer: C Explanation: MongoDB's document model allows different documents within the same collection to have varying structures, providing schema flexibility. Question 3. Which of the following is NOT a core data type in BSON used by MongoDB?
A) String B) Array C) Integer D) Graph Answer: D Explanation: BSON supports data types like String, Array, Integer, but not a dedicated 'Graph' type. Graph data structures are modeled through documents and references. Question 4. How does MongoDB differ from relational databases regarding schema? A) Requires predefined schema before data insertion B) Schemaless, allowing flexible document structures C) Enforces schema through strict constraints D) Uses only fixed schemas for consistency Answer: B Explanation: MongoDB is schemaless, meaning documents can have different structures within the same collection, offering flexibility compared to relational schemas. Question 5. Which CRUD operation in MongoDB is used to add multiple documents at once?
C) remove() D) drop() Answer: B Explanation: deleteMany() deletes all documents matching the specified filter. Question 8. What does the write concern in MongoDB define? A) The consistency level for read operations B) The level of acknowledgment requested from MongoDB for write operations C) The index to be used during write operations D) The security level for network communication Answer: B Explanation: Write concern specifies the level of acknowledgment requested from the server for write operations, affecting data durability and consistency. Question 9. Which type of index in MongoDB is used to support full-text search? A) Single field index B) Compound index C) Text index D) Geospatial index Answer: C
Explanation: Text indexes enable full-text search capabilities within MongoDB. Question 10. What is the purpose of creating a compound index? A) To index a single field with multiple values B) To combine multiple indexes for complex queries involving multiple fields C) To index text and geospatial data simultaneously D) To enforce uniqueness across multiple fields Answer: B Explanation: Compound indexes index multiple fields together, optimizing queries that filter on several fields simultaneously. Question 11. Which MongoDB command provides analysis of query execution and index usage? A) show indexes B) db.collection.stats() C) explain() D) profile() Answer: C Explanation: The explain() method shows detailed information about how MongoDB executes a query, including index usage.
B) Indexes all documents, including those with null values C) Indexes documents based on geographic location D) Indexes documents with a TTL (Time To Live) expiration Answer: A Explanation: Sparse indexes only include documents that contain the indexed field, ignoring documents where the field is missing. Question 15. What is the purpose of a TTL (Time To Live) index? A) To automatically delete documents after a specified period B) To restrict index access based on time C) To prioritize certain documents during queries D) To enforce security policies based on timestamps Answer: A Explanation: TTL indexes automatically remove documents after a certain expiration time, useful for cached or temporary data. Question 16. Which command adds a shard to an existing sharded cluster? A) sh.addShard() B) sh.enableSharding() C) sh.shardCollection()
D) sh.status() Answer: A Explanation: sh.addShard() adds a new shard to an existing sharded cluster. Question 17. What is the primary purpose of a shard key? A) To uniquely identify documents within a collection B) To determine how data is distributed across shards C) To enforce data consistency D) To improve the performance of aggregation pipelines Answer: B Explanation: The shard key determines how data is partitioned and distributed among shards in a sharded cluster. Question 18. Which shard key characteristic is most desirable for effective sharding? A) Low cardinality B) Monotonically increasing values C) High cardinality and even distribution D) Fixed values across all documents Answer: C
Question 21. Which security mechanism in MongoDB uses a challenge-response authentication protocol? A) LDAP B) SCRAM (Salted Challenge Response Authentication Mechanism) C) TLS/SSL D) X.509 certificates Answer: B Explanation: SCRAM is an authentication mechanism that uses a challenge- response protocol to verify user credentials securely. Question 22. What is the default authentication mechanism in MongoDB? A) LDAP B) SCRAM-SHA- 1 C) x. D) Kerberos Answer: B Explanation: MongoDB's default authentication mechanism is SCRAM-SHA-1, providing challenge-response authentication.
Question 23. Which built-in role provides full administrative access to all resources in MongoDB? A) readWrite B) dbAdmin C) root D) readAnyDatabase Answer: C Explanation: The root role provides full administrative privileges on the entire MongoDB deployment. Question 24. How can network traffic be secured in MongoDB? A) Use plain TCP connections B) Enable TLS/SSL encryption C) Disable authentication D) Use unencrypted FTP connections Answer: B Explanation: TLS/SSL encrypts network traffic, ensuring secure communication between clients and servers. Question 25. Which MongoDB security feature encrypts data stored on disk? A) TLS/SSL
D) Hashed index Answer: C Explanation: Geospatial indexes support spatial queries based on location data. Question 28. What is a major impact of creating indexes on write operations? A) Improved write latency B) No effect on write performance C) Increased write latency due to index maintenance D) Decreased storage requirements Answer: C Explanation: Indexes add overhead during write operations because the index structures must be updated, potentially increasing latency. Question 29. Which command provides a snapshot of the current status of a replica set? A) rs.status() B) db.serverStatus() C) sh.status() D) db.stats() Answer: A
Explanation: rs.status() provides detailed information about replica set status, including member health and election info. Question 30. In MongoDB, what is the role of an arbiter in a replica set? A) Stores data and acts as a secondary B) Participates in elections but does not hold data C) Manages data replication D) Handles read operations only Answer: B Explanation: An arbiter votes during elections but does not store data, helping maintain quorum. Question 31. Which read preference mode directs read operations to the primary node only? A) primary B) secondary C) primaryPreferred D) nearest Answer: A Explanation: The primary read preference directs all read operations to the primary node.
A) To serve as a backup in case the primary fails B) To be excluded from read operations and used for specific tasks like reporting C) To participate in elections but not store data D) To handle only write operations Answer: B Explanation: Hidden members are not visible to clients for read operations and are often used for specialized roles like analytics. Question 35. Which feature allows for data to be pre-split into chunks before sharding begins? A) Chunk migration B) Pre-splitting C) Zone sharding D) Balancer Answer: B Explanation: Pre-splitting creates chunks at collection sharding setup, helping distribute data evenly from the start. Question 36. What is the main benefit of zone sharding in MongoDB? A) Automatic data encryption B) Fine-grained control over data placement based on tags
C) Improved write performance only D) Simplifies index management Answer: B Explanation: Zone sharding allows administrators to assign specific data ranges or tags to particular shards, enabling geographic or logical data placement. Question 37. Which command is used to enable sharding on a specific database? A) sh.enableSharding() B) sh.shardCollection() C) sh.addShard() D) sh.status() Answer: A Explanation: sh.enableSharding() activates sharding for a database. Question 38. When creating an index, what does setting the "sparse" option do? A) Ensures the index is created on all documents, including those with null fields B) Creates an index only on documents containing the indexed field C) Enforces uniqueness across all documents D) Automatically deletes expired documents Answer: B
Question 41. Which of the following is a built-in role in MongoDB providing read and write access to a specific database? A) admin B) readWrite C) root D) readAnyDatabase Answer: B Explanation: readWrite grants read and write permissions on a specific database to users. Question 42. How can MongoDB be configured to only accept connections from trusted IP addresses? A) Use role-based access control B) Configure network firewalls and IP whitelisting C) Enable sharding D) Use sparse indexes Answer: B Explanation: Firewalls and IP whitelisting restrict network access to trusted sources.
Question 43. Which encryption method is used by MongoDB to secure data at rest? A) SSL/TLS B) WiredTiger encryption C) Kerberos encryption D) LDAP encryption Answer: B Explanation: WiredTiger supports encryption at rest, encrypting data stored on disk. Question 44. What is the effect of creating a multikey index in MongoDB? A) Indexes on multiple fields simultaneously B) Supports indexing on arrays by indexing their elements C) Ensures uniqueness across multiple documents D) Limits index size to a single key Answer: B Explanation: Multikey indexes support indexing array fields, allowing queries on array elements. Question 45. Which command is used to drop an index from a collection? A) db.collection.dropIndex()
